Articulated fairing



Nov. 2l, 1950 F. c. EAsTMAN ARTICULATED FAIRING 2 Sheets-Sheet l Original Filed May l0, 1948 l?? ven [01": Fred C. fas/mdf! Nov. 21, 1950 F. c. EASTMAN ARTICUL'ATED FAIRING 2 Sheets-Sheet 2 Original Filed May 10, 1948 QN mw Patented Nov. 2l, 1950 ARTICULATED FAIRING Fred C. Eastman, Marblehead, Mass., assignor to United Shoe Machinery Corporation, Flemington, N. J., a, corporation of New Jersey Original application May 10,l 1948, Serial No. 26,116. Divided and this application February 23, 1949, Serial No. 77,810

4 Claims. V(Cl. Sil-37.5)

This invention relates to articulated fairings 'or covers for guns which project from an airplane ing overlapping parts which were held togetherV by springs or the like and diiculty has been experienced because of excessive friction between those parts when the gun was turned to extreme positions.

Accordingly an object of the invention is to provide an improved pressure control mechanism Vfor holding the parts of afairing together.

In accordance with this object a feature of the invention relates to an automatic mechanism for this purpose which holds the parts of the fairing closely together but which relieves the pressure between these parts as they are moved to extreme positions.

These and other features of the invention will best be understood from a consideration Vof the following specification, taken in connection with the accompanying drawings, in which Fig. 1 is a side elevation of agun support with an associated fairing shown in section;

Fig. 2 is a transverse vertical section through a gun adaptor on the line II-II of Fig. 1;

Fig. 3 is a view similar to Fig. 1 but with the guns tilted upwardly; and

Fig. 4 is an enlarged horizontal section, through the tip of the fairing, taken on the line IV-IV .at the right end of Fig. 3.

venience, will be called a ball I4 (Fig. 1), comprises a zone through a sphere. Associated with this isa member which will be called a ring I6 and a bullet-shaped point portion I8 hereinafter called the point, which is provided with a tip I9. Openings (not shown) in the point are alined with the guns. The ring is provided with an and the like.

inner edge member 20, the inner surface of which is spherical so that it may slide on the outer surface of the ball I4. The outer end of the ring is provided with a similar internal member 22, the exposed surface of which is spherical to coact with a spherical end portion 24 on the point I8, the latter being urged inwardly against the ring by a hydraulic mechanism to be later described.

The ball is made up of an inner ring 26 and an outer ring 28 joined by a sheet-metal, frustoconical portion 30 as well as by an outer spherical portion 32. The inner ring is bolted to a ringlike channel 34 secured inside a corresponding circular opening in the airplane wall 35.

The gun mount is supported at the top by a. bracket 36 attached to the outer ring 28 of the ball and at the bottom by a xed gear segment 38 on top of a limit switch casing 40 which is carried on top of a supporting bracket 42 which extends between the inner and outer rings 26, 28.

Pivoted for movement about a substantially vertical axis 44 is a gun column 46 in the form of an irregularly shaped casting which is suppliedwith upper and lower pivot pins receivedy Within bearings 48 and 50. The upper bearing 48 comprises reversely arranged conical rolls to take the thrust of the column either up or down. This bearing 48 is carried by the bracket 36 while lthe lower bearing v5I) which serves as a pivot is carried on the gear segment 38. Rotation imparted to a pinion '52 engaging the teeth 54 on the gear segment 38 swings this column about its axis 44 to obtain movements of the guns in azimuth and the power for this swinging movement is obtained from a direct current motor 56 mounted on the column and which is connected by reducing gears to the pinion 52.

The gun adaptor I2 is pivoted on the gun column on a horizontal axis 60 to provide movements in elevation and has a gear segment 62 centered on the axis 60 so that changes in elevation may be effected by an electric motor 64 supported on the column 46 and connected by reduction gears (not shown) to a pinion 66 which `meshes with the teeth of the gear segment 62.

It will be noted from Fig. 2 that the gun adaptor is provided with chutes 68 and I0 which are directly above a passageway I2 provided at the bottom of the bullet-shaped point I8, thus permitting disposal of cartridge casings, belt links A camera I4 is supported on a bracket attached to the forward end of the adaptor andV is pointed at the target through openings I6 and 18.

3 To compensate for the obvious unbalance of the adaptor assembly I2 and the guns I0, an equilibrator has been provided which comprises a cylinder 80 pivotally connected at its right end at the point to brackets. 82 upon the gun adaptor. The equilibrator is provided with a piston 84 having a piston rod 86 joined to a yoke 88 pivoted at 90 to the gun column 46. Oil |02 under pressure from an accumulator 92 vis delivered through a pipe 94 (Fig. 1) to the cylinder portion 96 which lies at the rod Aside of `the piston 84. The accumulator 92 is supported in a ring-like bracket 98 pivoted to the'brackets 82 on the adaptor. The pressure upon the oil |02 within the accumulator 02 is maintained by providing air pressure through -a flexible pipe |04 to one side of a flexible diaphragm |06 within the accumulator. The pipe |04 is joined to an air storage tank |08 which is supplied from a motor driven compressor ||0. It will be understood that the hydraulic system operating. from the'accumulator 92 to the cylinder .80 renders it .easy to `avoid creep. `At the same time it is v.possible to maintain exactly the .desired pressure in theaccumulator 92 by maintaining .a suitable air pressure against the diaphragm |06. As the .gun is moved down, the pressure increases in the `area .9.6 but the leverarm between the `center 60 and the axis of the cylinder 80 decreases, .thus 'leaving the torque .substantially constant.

When the guns are pointed at an extreme angle, .the A.changein relation between the point I8 and vthe base of the ball I4 effects a change in the straight line distance between the center of the ball I4, for example, and .the .tip of the point. Some yieldable arrangement must, .there- .fore, be kprovided for holding .the point I8 in contact .with the ring I6 .and .consequently holding -the ring I6 against the vball I4. It was found too that the friction between .these fairing parts, at o1 near the positions of .considerable vangular .displacement, was very much increased by any or- .dinary spring arrangement which might be devised for .holding them together and this change (was sufficient to greatly `increase the load yupon the .motors 56 and 64 which produce the change in displacement.

Accordingly, a hydraulic .system has been .provided -for holding the point I8 inwardly against the ring I6 and this system includes ahydraulic cylinder ||2 which is slidable within an inner Atube- |14 vclamped `at `I I6 to the outer end of the ladaptor I2 while the cylinder is attached to the point .|8.. `'Surrounding the tube I|4 is an outer ...tube lr-which is slidable on the inner tube and the outer end of this outer tube ||8 is fastened to a cross partition in the -point I8. On this cross partition |20., are forwardly extending vbrackets |2| (Fig. 4) holding .a pin |22 on which ,the tip I 0 is tiltably secured by means of parallel ribs |23. Rigidly secured to a web between the YribsJZ, is a hook |24 (Fig. 3) `adapted to engage a cross pin |25 which issecured to the end .of the cylinder II2 and this hook may be disengaged by tilting the tip about the pin |22.

Accidental tilting of the tip I9 is prevented by the end of a stub arm |29 on a retaining latch |26 pivoted between ears extending rearwardly from the ribs |23 and `connected by a link |21 to a push button |28 at the end of the tip. When it is desired to remove the point I8 .of the fairing the button |28 is pushed inwardly against a coil spring thus moving the stub arm I 20 aside and permitting the tip I9 to be tilted `around its pivot |22 so as to drop the hooli |24 y from the cross pin |25 at the end of the cylinder. The point I8 and its cap I9 may then be withdrawn axially, with the outer tube II8 sliding on the inner tube II4. When the button is not depressed, its spring urges the latch |26 clockwise, as viewedin Fig. 3, to a position determined by contact @of along arm |3I, on the latch, with the pin |22, thus holding the end of the stub arm |29 in such a position over the cross pin |25 that it prevents tilting of the tip I9.

Within the cylinder ||2 is a piston |30 connected by a cross pin |32 to the inner tube ||4 and hence to the adaptor. Fluid under pressure lls .the space between the piston and the left end of the cylinder. As the point portion I8 moves outward with respect to the inner tube II4 the space between the piston |30 and the cylinder head decreases thus increasing the pressure acting to hold portion I8 inward and increasing the friction between portion I3 and the .ring I6 andbetween the ring and the ball I4 with a resulting heavy load on the driving motors as the gun is trained. To avoid this the cylinder |2.is connected by pipes |34 and |36 to a cylinder |68 which is mounted on the adaptor I2 vand. to a Ycylinder |40 (Fig. 3) which is mounted on the gun column 46. Each of these cylinders .hasa .piston having an attached roller which rides, in the lrst instance, against a cam |42 fixed on the gun column 46 and in the second instance, against a .cam |44 attached to the gear segment 3S which is mounted on the fixed bracket 42 .attached to the plane. By means of this arrangement the pressure within thev cylinder `Ii'and hence in cylinder I|2 is held at the lde- .sired maximum as the guns are pointedstraight to the rear and is decreased as the guns .are elevated vor depressed, this following from the shape 4of .the cam |42. A-similar shape of the cam |44 causes the pressure to be maximum within the cylinder |40 and hence in cylinder II2 when the guns .are pointed directly to the rear and decreases this eiect as the guns are swung to one .side or the other. Consequently, the pressure in 'the hydraulic system is relieved as the guns and the portion I8 are swung away from center 30 as -to maintain a free `turning engagement between Ythe point |-8 vand the ring Aand betweenthe ring .and the ball.

Any suitable .system may be employed for the yremote control of the motors 55 Vand 64 so that the guns `may .be laid .or directed at the target i-n .accordance with the wishes of a gunner who operates a sight (not shown) capable of being Iswung .in azimuth and tilted in elevation. During these movements Y of the gun the pressure which holds together the parts I4, I6 Yand |8 of the articulated fairing will be automatically controlled so as to prevent the air stream from separating these parts by reason of any undue slackening of the pressure required to hold the parts together and at thesame time sufficient pressure will always be maintained within the cylinder II2 to lhold them together but without causing any undue friction. The feeding of ammunition to the guns can be carried out automatically by means of any well-known system which delivers the cartridges automatically from a .storage receptacle ,inside the plane itself and .allows 'the vlinks of the conveyor chain as well vas the cartridge casings and any duds to fall out through thechute 11.

This application is a divisions of application serial No. .26,116, filed May .10, 1948 in my name 5 for improvements in Remote Control of Guns for Airplanes.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In an airplane having an opening in its wall, a gun pivotally supported to project through said opening, a sheath covering the gun and surrounding said opening, said sheath comprising sections articulated with respect to one another to permit the gun to be laid, means for drawing in the outer section toward the plane, and means for decreasing the force with which said outer section is drawn in as such section is moved away from a mid position.

2. In an airplane having an opening in its wall, a. spherical member secured around said opening and projecting therefrom, a ring tting and sliding on said spherical portion, a gun supported to project beyond said spherical portion and extending through the ring, an outer fairing about lsaid gun having a spherical joint with the outer end of said ring, a piston and cylinder connection between said outer fairing and the gun, uid under pressure in said cylinder to draw the fair- 6 ing inwardly, an auxiliary cylinder connected to the rst cylinder, and means for decreasing the volume of the auxiliary cylinder as a mid position is reached while increasing its volume as the gun is deected.

3. In an airplane, an opening, a gun projecting from said opening and pivotally mounted for movements with respect to the plane, an articulated sheath surrounding said gun and connected to the plane, and means for holding the parts of said sheath together including means for increasing the holding force as a straight line position is reached and decreasing it during deflection away from that position.

4. In an airplane, an opening, a gun projecting from said opening and pivotally mounted for movements with respect to the plane, an articulated sheath surrounding said gun and connected to the plane around the opening therein, and means for holding the parts of said sheath together including means for decreasing the holding force during deflection either in elevat1on or azimuth.

FRED C. EASTMAN.

No references cited. 

